Improvement in ciboulab-sawing machines



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RALPH V. WHITING, OF ABINGTON,' MASSACHUSETTS, ASSIGNOR TO D.

B. GURNEY, OF THE SAME PLACE..

Lam Patent No. 68,137, dazed August 27,1867'.

IMPROVEMENT IN GIRGULAIVSAWING MACHINES.

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TO ALL WHOM IT MAY CONCERN:

Be itknown that I, RALPiI'V. WRITING, of Abington, in the county of Plymouth, and Stateof Massachusetts, have invented certain new and useful improvements in Board-sawing Machines and I do hereby declare that the follovving is a full and exact description thereof, reference being had to the accompanying drawings, and to the Vletters of reference'marked thereon. Y

The nature of my invention consists in arranging the weights which draw back the slide or carriage of a board-serving machine, in such a manner that when the carriage first starts to return the combined weights pull in one direction, and in aid of each other, but when the carriage has passed acertain distance, and has, with its load, acquired quite a momentum, the weights willact in opposition to each other, and thus cease to give additional velocity to the carriage, or, if desirable, they may act to' check the speed, or even to stop the carriage altogether. v

To enable others skilled in the art to make and use my invent-ion, I will proceed to give a description ofI its construction and use. In the drawings Figure 1 is a perspective view ofthe machine, all details not essential to the illustration of my invention being omitted. Y

Figure 2 is a vertical section of the'machine. i l

A represents a door 1or base, upon which I build my machine. B B B B, legs or supports for the machine. C, the table or bed, through which `the saw works. D is a slide or carriage, upon which the log is carried. All ofthe above parte may be made of any suitable material, and their construction may vary with the char- `noter of the work to be done. I have not entered upon a particular description of them for the'reason that my invention relates entirely to the method of Weighting the slides on the carriage I). i

The method in common use to cause the slide to run back, after it hasV carried the log past the saw, is to attach a cord, S, with a weight, T, near to the rear end, as at N,iiig. 2. The object of this arrangement is that a weight acting in this manner must be quite heavy in order to start thel slide back, and having once started it., it still continues to act with full force, thus constantly accelerating the motion of the slide, so that at th'e end of its ways its motion will be very rapid, or if the weight is so light that the slide does not acquire a rapid motion, the whole time required for it to return Awill be too long for the most economical working of the machine. '.lo obviate this diiiiculty I attach a secondcweight, W, by a cord, II, to a central point, N', o nn the slide, so thatrwhen the slide has passed by the saw, as represented by the dotted lines at D', tig. 2, both the weights pull in Ythe same direction until the point of attachment of the linevH has passed by the pulley K, then the weight* W acts in opposition to the weight T, so that the motion of the slide is checked.

The great advantage of thisarrangement is, that I havethe two weights to start thc slide, and thus to cause it to move rapidly athrst, and yet not give it an accelerated motion, for the weight W, as stated above, begins to act in opposition to the weight T when the slidc has passed a certain part of its backward journey, thus checking its velocity. By this arrangement this backward journey of the slide is made in considerable less 'time thanvcan be accomplished by the old method of weighting. I make a saving of time, for the whole operation of sawing, of about thirty per cent.

What I claim as my invention, and desiro to secure by Letters Patent,is

So arranging the weights which draw back thc.slide or carriage of a board-sawing machine, that when the f carriage rst starts to return, the combined weights pull in one direction and in aid of each other, but ivhcn the carriage has passed a certain distanceand.has with its load acquired quite a momentum, the weights will actin opposition to each other, and thus cease to give additional `velocity to the carriage, substantially as described and for the purpose set'forth. 1

RALPH V. WHITING.

Witnesses:

Issue Hanser, .J..E. Knr'rn. 

